The scanners are extensively used to scan text or graph to a computer accessible format. The document to be scanned is placed atop a glass mounted on a top lid of the scanner.
FIGS. 1 and 2 shows two kinds of prior art glass and lid assembly for scanner. The assembly comprises a top lid 1a, a glass plate 10a, and a double-side tape 11a. The top lid 1a has a flat surface defining a window 13a to form an apertured surface 14a thereon. One side of the double-side tape 11a is attached to the peripheral of one side of the glass plate 10a and another side of the double-side tape 11a is attached to the apertured surface 14a such that the glass plate 10a seals the window 13a. As shown in FIG. 1, the assembly further comprises an ornamental plate 12a attached to another side of the glass plate 10a to hide the double-side tape 11a and function as a ruler. The glass plate 10a can be attached to an outer side of the aperture surface 14a as shown in FIG. 1, or attached to an inner side of the aperture surface 14a as shown in FIG. 2.
However, the above-mentioned glass and lid assembly for scanner has complicated assembling and the use of double-side tape 11a increases cost. The glass and lid assembly requires additional pressing tool for assembling. The overall assembly is wasted if one of its components has defect. Therefore, the above-mentioned glass and lid assembly is not suitable for low end scanners.